feat(genius): load song metadata, lyrics, and artwork

Search hits omit album covers and artist images. The worker now reads the full song and artist, stores the description, and leaves Genius image URLs unchanged on mobile.

Co-authored-by: Cursor <cursoragent@cursor.com>

deploy/.env.example

@@ -44,6 +44,10 @@ LOG_LEVEL=info
 SUPPORTED_LOCALES=ru,en
 MIN_ANDROID_VERSION_CODE=0
 
+# Genius: empty token disables enrichment. Queue and controls: Admin → Sources.
+GENIUS_ACCESS_TOKEN=
+GENIUS_REQUEST_INTERVAL=2s
+
 # --- Самообновление Android (M5) ---
 # Пусто — install.sh и update.sh возьмут из origin клона (например, https://gitea.example.com и owner/pipu-music).
 # Если сервер не видит Gitea по внешнему адресу, укажите внутренний: GITEA_URL=http://10.0.0.5:3000